The course of the river flows through World Heritage listed high altitude rainforest, noted for its Antarctic Beech; and then through lower altitude subtropical rainforest, including trees such as Red Cedar and Small leaf fig.
Parts of the forest were once logged for various timbers including red cedar, bunya pine and hoop pine.
In 1868, the Queensland Government opened up large areas of land for settlement in the Caloundra area which became home to pioneers and timber cutters seeking red cedar wood.
Prior to European settlement the rich volcanic soil on the ridge supported a sub-tropical rainforest, which contained timbers that were in high demand, including red cedar, tallowwood and hoop pine.
The surrounding rainforest contains giant kauri (Agathis microstachya), Red cedar trees and flowering umbrella trees (Schefflera actinophylla).
In the late 1870s and early 1880s, European redcedar cutters and Chinese that were prospecting for gold arrived in the region.
With an abundant supply of red cedar amongst other tree species, the first industry to flourish in the area was timber cutting.
Both chairs are made from red cedar, the vice-regal chair in 1856 and the president's chair in 1886.
Toona ciliata, an tree in the mahogany family native to Asia and Australia
Particularly rich was the soil of the Redland Bay District which is said to have had lush rainforest complete with prized red cedar.
It grows best in an environment with high light levels, however in the relative darkness of the rainforest understory, it is less susceptible to attack by the Cedar Tip Moth
The Australian Red Cedar growing in the Tumbulgum area attracted timber-cutters from the 1840s and by the early 1860s a small community and river port had been established on the northern side of the Tweed River where it met the Rous.
Sub Tropical mixed Broad-Leaved Hill Forest is the forest type in the area comprising: Alnus nepalensis (Uttis), Castanopsis (Kattus), Macaranga (Malata), Engelhardia spicata (Mahua), Michelia (Champ), Toona ciliata (Tooni), Machilus (Kawla), Symplocos (Kharane) and Cinnamomum (Sinkoli).
Significant tree species include Red Cedar, Myrtle Ebony, Deciduous Fig, Citronella, Silver Quandong, Whalebone Tree and Bollygum, many of which are near their southernmost limit of natural distribution.